1.Field of the Invention
This invention relates to stepladders. More particularly it concerns a new form of stepladder base designed to provide high lateral stability.
2. Description of the Prior Art
Although ladders are not rated high on the Consumer Product Safety Commission list of hazardous products, there is a need to improve upon their construction to diminish hazard to users. With stepladders, a prominate hazard is lack of lateral stability so that when a climber on the ladder reaches outward to perform a task or push laterally, the ladder may not resist both static and dynamic loading or shifting weight thereby resulting in a tilting accident.
It has been established that a primary element in stepladder stability is the total width of the ladder base. Another factor is the climbing height for any particular ladder size. Hence, stepladder stability can be improved by increasing the width of the base of a ladder, as opposed to adding to the length of its steps. Also, stability is increased by making the distance between the highest step on the ladder and its top a minimum of 18 inches.
It is known to provide ladders with outriggers to provide lateral stability as shown by U.S. Pat. Nos. 1,385,319; 3,508,628 and 3,891,054. Additional patents showing the state of development of the art includes:
______________________________________ U.S. Pat. No. 451,893 1,102,428 1,235,696 485,900 1,135,336 1,415,791 636,444 1,135,763 1,526,654 1,610,596 2,324,414 2,997,127 1,924,213 2,364,048 3,786,900 ______________________________________
Not withstanding the numerous improvements in this field as indicated by the listed patents, there is need for further advance in the art. For example, many of the devices of the prior art unduly complicate the ladder structure. Also, many of them are cumbersome, are poor as to shipping space economy and subject to much shipping damage.